Baby is looking more adorably baby-like as the eyes move closer together, and the ears are settling into their final position. The nervous system is developing and fine-tuning, leading to the arrival of reflexive actions such as sucking. At the end of the week, the vocal cords have formed, although you won't get to hear their effects for months yet. The organs are formed and functioning, for instance the pancreas is producing insulin, the pituitary gland is producing hormones, and bone marrow is producing white blood cells. The baby is now the size of a large plum, about 3.15" long and 1 ounce at the end of the week.

Pregnancy Symptoms You May Feel During Week 12

Many symptoms are lessening or leaving altogether, such as nausea, tender breasts, and fatigue, as the first trimester draws to a close.

While many of the most troublesome pregnancy symptoms of the first trimester have ended, a new one may be starting. Dizziness or fainting might be a problem and is due to the hormone, progesterone increasing blood flow and relaxing blood vessels. Additionally, pregnant women often suffer from lowered blood sugar, which also can contribute to dizziness. To counteract this tendency, make sure to eat frequent small meals, make sure you are getting enough rest, and always stand up slowly.

Your uterus is now the size of a large grapefruit, and is moving from the bottom of the pelvis to the middle of the abdomen, which should relieve some of the pressure on the bladder thereby lessening the frequency of urination for awhile.

Visit With the Obstetrician

Now that the uterus has grown to the grapefruit- sized range and is rising up into the abdomen, the doctor will be palpating the uterus through the abdomen. Every visit, this will be a main component, as the physician will determine where the uterus is at, and later even, the position of the fetus from feeling on your ever-protruding tummy. Ask what you are measuring and record it in your pregnancy journal, along with your weight.

Preparing for Baby

One of the big decisions all new parents must make: cloth or disposable. There is a ton of information out there on what is best for the environment, what is best for baby, and best for parents, too. Then there is question of which ones? Read up on it now, talk to other new parents to see what their experiences and reasons behind their decisions were. Then if choosing cloth, start researching the best deals. Will you buy all your own or use a diaper service? Find out the practical side too. How to clean, how to do nighttime diapering, dealing with messy bowel movement stains, how to do cloth when you are on the road, or have a child in daycare. If you decide to go with disposable, look into bulk buying and if it's really the better deal.

Pregnancy Lifestyle

Since the nausea and queasiness of the first trimester should be subsiding now, it's a good time to start looking seriously at diet and nutrition issues. Pregnancy isn not a free pass to a total feeding frenzy. It is definitely not as simple as "eating for two", either. Today, a woman will need to take into account her body mass index, or BMI, to determine what her ideal weight gain will be. An obese woman might even be advised to lose some weight, through safe and sane methods, during her pregnancy. Talk to your doctor about what a healthy weight goal is for your pregnancy.

The best way to plan for a healthy weight gain is not to go with fatty or sugary empty calories. Have a balanced diet of a variety of fruits, vegetables, whole grains and proteins. Since frequent small meals are best, plan ahead for healthy snacks. Nuts, raisins, cheese, yogurt, and fruit are good choices.

Plan for about 300 extra calories daily, in general. The average weight gain is around 25-35 pounds, but again, that depends on the mother's weight and BMI. Click here to calculate your ideal weight gain with our free pregnancy weight gain calculator

Hi i'm 12 weeks and 5 day's pregnant. ive had morning sickness since i was 6 weeks gone, but still have it now, plus nausea, emotional, sore breasts. i have them all. but, i never did with my other 2 children. i know every pregnancy is different as i'm finding out. i'm always tired, don't feel like going to work, just want to lay down and sleep all the time.

Hi. i have two kids. with them i found out i was pregnant right away when the tests came out positive quickly after my first missed period. but, i had a ending period june 28th. then on july 10th had unprotected sex on the 22nd and 23rd of july. i thought it was implantation bleeding, but after the 3rd day i had a heavy flow lasting 5 days totaling 7 days. so i never thought of being pregnant after because it was a one time thing with my ex and haven't had sex. now it's sept 19th, and i haven't had a period. these past four days my stomach is feeling bloated, my breasts are bigger, and i'm feeling jumping movements. so i'm thinking i'm pregnant. i took 2 ept home pregnancy tests. both were negative. can i be pregnant? i feel so out of the norm and feel pregnant. just want to see if anyone has experienced that?

Guest Sep 23, 2014 12:26:01 AM ET

I am now 12 weeks, and 5 days pregnant, so i got pregnant around july 2nd. i took several home pregnancy tests throughout july and didn't get a positive test result, until the middle of august. i have been watching the show, "i didn't know i was pregnant" on tlc, and there have been women who took pregnancy tests because they thought they might be pregnant but always got a negative result, or who also had a normal period throughout the pregnancy! hope this helps some!

I am 12 weeks pregnant and my baby is already 2oz and about 5 inches long. its looking like a girl but cant be for sure until my next ultrasound. so apparently i'm going to have a large baby im guessing. i'm ready. my last two kids were 8.1 and 7.4 lbs. bring it on.

I'm 12 weeks 5 days and i seem to just have the physical symptoms like exhaustion, nausea and tender breasts. i have not noticed any difference in my emotional state yet. i guess i should be happy about that. i am actually handling it pretty well. i'm thankful for that.

I feel fine my self. my belly has grown a lot. feeling little flutters now. still falling asleep at 10ish and waking at 12:30 then 6:30 in morning. my nipples aren't sore now at all. i've been very irritable and snappy though. x

I am 12 weeks 4 days and i am still very tired. i had sore breasts from before i knew i was prego up until about 10 weeks and that turned into nipple soreness. also i am very bloated, and have had about 3 days where i was super hungry, the rest of the time i make myself eat. i was diagnosed with a sch at 9 weeks. i go in for a scan friday so hope all is well and i hope to feel at least less tired asap.